#include <vector>

// 使用float类型表示实数
using Real = float;

// 材料元素模块中的常量
const int NDIM_IX = /* 定义NDIM_IX的值 */;

/**
 * @brief 质量添加子程序，用于处理节点动量、质量和能量沉积
 * @param velocity 速度数组（按自由度排列）
 * @param nodalMass 节点质量数组
 * @param elementList 元素索引数组
 * @param options 选项参数数组
 * @param scaleFactors 缩放因子数组
 * @param fieldValues 场值数组
 * @param elementVolume 单元体积数组
 * @param materialDensity 材料密度数组
 * @param stress 应力数组
 * @param stressIndex 应力索引数组
 * @param energySolution 能量解数组
 * @param elementType3D 3D单元类型数组
 * @param numNodeMomentum 节点动量沉积数量
 * @param numElementMass 单元质量沉积数量
 * @param numElementEnergy 单元能量沉积数量
 * @param timeStep 时间步长
 * @param numDegreesOfFreedom 每个节点的自由度数
 */
void ADDMAS(std::vector<std::vector<Real>>& velocity,
            std::vector<Real>& nodalMass,
            std::vector<int>& elementList,
            std::vector<std::vector<int>>& options,
            std::vector<std::vector<Real>>& scaleFactors,
            std::vector<Real>& fieldValues,
            std::vector<Real>& elementVolume,
            std::vector<Real>& materialDensity,
            std::vector<Real>& stress,
            std::vector<int>& stressIndex,
            std::vector<std::vector<Real>>& energySolution,
            std::vector<int>& elementType3D,
            int numNodeMomentum,
            int numElementMass,
            int numElementEnergy,
            Real timeStep,
            int numDegreesOfFreedom) {

    // 1. 节点动量沉积
    for (int i = 0; i < numNodeMomentum; ++i) {
        int node = elementList[i];
        int direction = options[0][i] - 1;  // Fortran转C++索引
        int fieldIndex = options[1][i] - 1;
        
        Real scaleFactor = scaleFactors[0][i];
        Real oldValue = scaleFactors[1][i];
        Real currentRate = fieldValues[fieldIndex];
        
        // 计算动量增量
        Real momentumIncrement = 0.5 * timeStep * (currentRate + oldValue) * scaleFactor;
        
        // 更新缩放因子的旧值
        scaleFactors[1][i] = currentRate;
        
        // 计算质量索引（考虑自由度）
        int massIndex = direction + numDegreesOfFreedom * (node - 1);
        
        // 更新节点速度（动量守恒）
        velocity[direction][node - 1] = 
            (velocity[direction][node - 1] * nodalMass[massIndex] + momentumIncrement) / 
            nodalMass[massIndex];
    }

    // 2. 单元质量沉积
    for (int i = 0; i < numElementMass; ++i) {
        int elementIdx = elementList[numNodeMomentum + i];
        int fieldIndex = options[1][numNodeMomentum + i] - 1;
        
        Real scaleFactor = scaleFactors[0][numNodeMomentum + i];
        Real oldValue = scaleFactors[1][numNodeMomentum + i];
        Real currentRate = fieldValues[fieldIndex];
        
        // 计算质量增量
        Real massIncrement = 0.5 * timeStep * (currentRate + oldValue) * scaleFactor;
        
        // 更新缩放因子的旧值
        scaleFactors[1][numNodeMomentum + i] = currentRate;
        
        // 获取单元类型
        int elementType = elementType3D[elementIdx - 1];
        
        if (elementType < 2) {
            // 砖块单元或退化四面体
            if (/* 检查是否为退化四面体 */) {
                // 退化四面体: 质量均分到4个节点
                Real nodalMassIncrement = 0.25 * massIncrement;
                for (int j = 0; j < 3; ++j) {
                    int node = /* 获取节点索引 */;
                    if (node != 0) {
                        int massBaseIndex = numDegreesOfFreedom * (node - 1);
                        nodalMass[massBaseIndex] += nodalMassIncrement;
                        nodalMass[massBaseIndex + 1] += nodalMassIncrement;
                        nodalMass[massBaseIndex + 2] += nodalMassIncrement;
                    }
                }
                // 处理第4个节点
                int node = /* 获取第4个节点索引 */;
                if (node != 0) {
                    int massBaseIndex = numDegreesOfFreedom * (node - 1);
                    nodalMass[massBaseIndex] += nodalMassIncrement;
                    nodalMass[massBaseIndex + 1] += nodalMassIncrement;
                    nodalMass[massBaseIndex + 2] += nodalMassIncrement;
                }
            } else {
                // 8节点实体单元: 质量均分到8个节点
                Real nodalMassIncrement = 0.125 * massIncrement;
                for (int j = 0; j < 8; ++j) {
                    int node = /* 获取节点索引 */;
                    if (node != 0) {
                        int massBaseIndex = numDegreesOfFreedom * (node - 1);
                        nodalMass[massBaseIndex] += nodalMassIncrement;
                        nodalMass[massBaseIndex + 1] += nodalMassIncrement;
                        nodalMass[massBaseIndex + 2] += nodalMassIncrement;
                    }
                }
            }
        } else if (elementType == 3) {
            // 4节点四面体
            Real nodalMassIncrement = 0.25 * massIncrement;
            for (int j = 0; j < 3; ++j) {
                int node = /* 获取节点索引 */;
                if (node != 0) {
                    int massBaseIndex = numDegreesOfFreedom * (node - 1);
                    nodalMass[massBaseIndex] += nodalMassIncrement;
                    nodalMass[massBaseIndex + 1] += nodalMassIncrement;
                    nodalMass[massBaseIndex + 2] += nodalMassIncrement;
                }
            }
            // 处理第4个节点
            int node = /* 获取第4个节点索引 */;
            if (node != 0) {
                int massBaseIndex = numDegreesOfFreedom * (node - 1);
                nodalMass[massBaseIndex] += nodalMassIncrement;
                nodalMass[massBaseIndex + 1] += nodalMassIncrement;
                nodalMass[massBaseIndex + 2] += nodalMassIncrement;
            }
        } else if (elementType == 2) {
            // 10节点四面体
            // 角节点质量分配
            Real cornerMass = massIncrement / 36.0;
            for (int j = 0; j < 4; ++j) {
                int node = /* 获取角节点索引 */;
                if (node != 0) {
                    int massBaseIndex = numDegreesOfFreedom * (node - 1);
                    nodalMass[massBaseIndex] += cornerMass;
                    nodalMass[massBaseIndex + 1] += cornerMass;
                    nodalMass[massBaseIndex + 2] += cornerMass;
                }
            }
            // 边中节点质量分配
            Real edgeMass = 4.0 * massIncrement / 27.0;
            for (int j = 4; j < 10; ++j) {
                int node = /* 获取边中节点索引 */;
                if (node != 0) {
                    int massBaseIndex = numDegreesOfFreedom * (node - 1);
                    nodalMass[massBaseIndex] += edgeMass;
                    nodalMass[massBaseIndex + 1] += edgeMass;
                    nodalMass[massBaseIndex + 2] += edgeMass;
                }
            }
        }
    }

    // 3. 单元能量沉积
    for (int i = 0; i < numElementEnergy; ++i) {
        int elementIdx = elementList[numNodeMomentum + numElementMass + i];
        int energyType = options[0][numNodeMomentum + numElementMass + i];
        int fieldIndex = options[1][numNodeMomentum + numElementMass + i] - 1;
        
        Real scaleFactor = scaleFactors[0][numNodeMomentum + numElementMass + i];
        Real oldValue = scaleFactors[1][numNodeMomentum + numElementMass + i];
        Real currentRate = fieldValues[fieldIndex];
        
        // 计算能量增量
        Real energyIncrement = 0.5 * timeStep * (currentRate + oldValue) * scaleFactor;
        
        // 更新缩放因子的旧值
        scaleFactors[1][numNodeMomentum + numElementMass + i] = currentRate;
        
        // 如果是类型1，需要乘以体积和密度
        if (energyType == 1) {
            int materialIdx = /* 获取材料索引 */;
            energyIncrement *= elementVolume[elementIdx - 1] * materialDensity[materialIdx - 1];
        }
        
        // 更新应力和能量解
        int stressOffset = stressIndex[elementIdx - 1] - 1;
        stress[stressOffset + 2] += energyIncrement;  // 第3个应力分量
        energySolution[0][elementIdx - 1] += energyIncrement;
    }
}